SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '159e018fcab377cbafbf04605708a55336ba67f148559e3ac2cbacf9b3722a08' 
  AND token = 'bveJYmkpDB/qv54rZZ4d+6vfo4D4mfCx67r8+K+vz4c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}